.\" Copyright (C) 2024 Tony Solomonik <tony.solomonik@gmail.com>
.\"
.\" SPDX-License-Identifier: LGPL-2.0-or-later
.\"
.TH io_uring_prep_ftruncate 3 "January 23, 2024" "liburing-2.6" "liburing Manual"
.SH NAME
io_uring_prep_ftruncate \- prepare an ftruncate request
.SH SYNOPSIS
.nf
.B #include <liburing.h>
.PP
.BI "void io_uring_prep_ftruncate(struct io_uring_sqe *" sqe ","
.BI "                             int " fd ","
.BI "                             loff_t " len ");"
.fi
.SH DESCRIPTION
.PP
The
.BR io_uring_prep_ftruncate (3)
function prepares an ftruncate request. The submission queue entry
.I sqe
is setup to use the file descriptor
.I fd
that should get truncated to the length indicated by the
.I len
argument.

Applications must define
.B _GNU_SOURCE
to obtain the definition of this helper, as
.I loff_t
will not be defined without it.

.SH RETURN VALUE
None
.SH ERRORS
The CQE
.I res
field will contain the result of the operation. See the related man page for
details on possible values. Note that where synchronous system calls will return
.B -1
on failure and set
.I errno
to the actual error value, io_uring never uses
.IR errno .
Instead it returns the negated
.I errno
directly in the CQE
.I res
field.
.SH SEE ALSO
.BR io_uring_get_sqe (3),
.BR io_uring_submit (3),
.BR ftruncate (2),